For enhanced safety, the front seat shoulder belts of the Mazda 3 are height-adjustable to accommodate a wide variety of driver and passenger heights. A better fit can prevent injuries and the increased comfort also encourages passengers to buckle up. The MINI Cooper Hardtop 4 Door doesn’t offer height-adjustable seat belts.
The Mazda 3 has standard Whiplash Reducing Headrests, which use a specially designed headrest to protect the driver and front passenger from whiplash. During a rear-end collision, the Whiplash Reducing Headrests system moves the headrests forward to prevent neck and spine injuries. The Cooper Hardtop 4 Door doesn’t offer a whiplash protection system.
The Insurance Institute for Highway Safety tests front crash prevention systems. With a score of 6 points, IIHS rates the Smart City Brake Support in the Mazda 3 as “Superior.” The Cooper Hardtop 4 Door scores only 4 points and is rated only “Advanced.”
Over 200 people are killed each year when backed over by motor vehicles. The Mazda 3 Turbo Premium Plus has standard Smart Brake Support that uses rear sensors to monitor and automatically apply the brakes to prevent a rear collision. The Cooper Hardtop 4 Door doesn’t offer backup collision prevention brakes.
The Mazda 3 offers all-wheel drive to maximize traction under poor conditions, especially in ice and snow. The Cooper Hardtop 4 Door doesn’t offer all-wheel drive.
The Mazda 3 Turbo Premium Plus has a standard 360-Degree Monitor to allow the driver to see objects all around the vehicle on a screen. The Cooper Hardtop 4 Door only offers a rear monitor and front and rear parking sensors that beep or flash a light. That doesn’t help with obstacles to the sides.
The Mazda 3 Select/Preferred/Carbon/Premium/Turbo’s blind spot warning system uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them. The Cooper Hardtop 4 Door doesn’t offer a system to reveal objects in the driver’s blind spots.
To help make backing out of a parking space safer, the Mazda 3 Select/Preferred/Carbon/Premium/Turbo’s standard rear cross-path warning system uses sensors in the rear bumper to alert the driver to vehicles approaching from the side, helping the driver avoid collisions. The Cooper Hardtop 4 Door doesn’t offer a cross-path warning system.
Both the Mazda 3 and the Cooper Hardtop 4 Door have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, front seatbelt pretensioners, front wheel drive, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, rearview cameras and driver alert monitors.
For its top level performance in IIHS driver and passenger-side small overlap frontal, moderate overlap frontal, side impact, roof strength and head restraint tests, its standard vehicle-to-vehicle front crash prevention system, its standard vehicle-to-pedestrian front crash prevention system, and its standard headlight’s “Good” rating, the Insurance Institute for Highway Safety grants the Mazda 3 its highest rating: “Top Pick Plus” for 2021, a rating granted to only 74 vehicles tested by the IIHS. The Cooper Hardtop 4 Door has not been fully tested, yet.